Production of glycols



-N. M. MNOOKIN PRODUCTION OF GLYCOLS Sept. 20, 1938.

Filed Sept. 21, 1936 IN VENT OR.

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retenes sept. 12o, reas F H i.. L

raonUcrroN or earns Nathan M. Mnookin, Kansas (City, Mo., asslgnor A to Synthetic Products, Enc., a corporation of url application september zr, rase, sensi No. man

24 Claims.

The present invention relates to improvements in methods for the hydrolysis of oleiin halide compounds oi lthe dihalide. and halohydrin types; and more particularly to an economical,

eiicient and continuous process for the production of glycols and other polyhydric alcohols from olen dihalides in which the halohydrin formed during the reaction is continuously SegreI gated and returned to the system for further present invention is a continuation-impart of my prior vcopending application' Serial No. 546,917, iiled June 25, 1931, which has matured into Patent No. 2,056,976.

Hitherto, in the production of glycols or other polyhydric alcohols by the hydrolysis of olein dihalides, chlorhydrins and the like, the-reaction has been effected in the presence of Weak alkalies or of soaps of strong bases and Weak acids such as the alkali and alkaline earth metal carbonates, bicarbonates, acetates, formates, phosphates and the like; but the reactions have been complicated and theyields reduced by side reactions and polymerizations resulting in the formation of vinyl compounds, resinous bodies, and other undesirable icy-products.

I have discovered that the undesirable side reactions and formation of undesired by-products may be avoided and a much increased, almost quantitative yield of the desired hydroxy-bodies secured by effecting the hydrolysis of olen halide compounds or haloh'ydrins in the presence of an acid while maintaining superatmospheric pressure and elevated temperature conditions. By operating inaccordance with the present invention I am able to secure yields of the polyhydric alcohol desired exceeding 90% and in general to the amount of 95% or more of,the theoretical yield. The side reactions, with the formation of vinyl halides, resinous and tarry polymerization products and other undesired by-products are substantially completely eliminated and the expense of operation is markedly reduced.

The reaction in accordance with the present invention may be illustrated in connection with its specific application to the' production of glycol from ethylene .dichloride and ethylene chlorhydrin.

In accordance with the present invention, ethylene dichloride is heated with an excess of water, say atleast ve times its volume and preferably about iifteen times its volume, the water being preferably slightly acidulated, suitably with hydrochloric acid. Other acids, such as sulfuric acid, acetic acid, phosphoric acid or the .like

treatment and completion of the reaction. The.

may be employed but the use of hydrochloric acid is preferred, as it is one of the products of reaction. The proportion of acid used is very slight, say one-half to one part of N/lO acidto parts by volume of-ethylene dichloride and 1500 parts by volume of water, or the acid'may be entirely omitted. The reacting materials are then heated under pressure to a temperature of at least C., and preferably above 135 C. The temperature may be carried as high as 200 C. or even higher, but in general temperatures above 200 C. are undesirable, as they result in side reactions with the formation of Various polymerizations and decomposition products. I have found temperatures of the order of to C. most desirable in use.

The speed of the reaction may likewise be accelerated by use of catalysts, as hereinafter more fully set forth.

` In carrying out the reaction, the mixture of constituents in the pressure receptacle is heated to the desired temperature, which is maintained until the reaction is completed. During the course of the reaction, the pressure in the receptacle rises, say to 225 lbs. or even higher, and then gradually diminishes as the reaction proseeds, finally dropping to 175 lbs. or lower. After completion of the reaction, the ve'ssel is cooled und the reaction mixture is found to be present as a clear aqueous liquid. The ethylene dichloridelis completely consumed and undesirable side products, such as aldehydes, tarry decomposition products and the like are negligible in amount. On distillation, the recovery of glycol is very close to theoretical, in excess of 90% and in general of 95% of the theoretical yield being secured. The chlorine of the ethylene dichloride is found to be substantially entirely present as hydrochloric acid. The hydrochloric acid may be neutralized, as with lime, to form a valuable by-product or may be utilized in any suitable manner.

If desired, the reaction may be halted at an intermediate point or on occasions it'may be necessary to stop it before completion. Insuch cases, the reaction mixture will be found to contain glycol and chlorhydrin. By reacting on the chlorhydrin with an excess of water in the same manner, the conversion into glycol may be completed.

As indicated above, hydrochloric acid is one of the products of reaction. If desired, the reaction may be initiated with the chlor-compound and water alone, the halogen acid resulting from hydrolysis developing the acidity required for proper conduct ot the reaction. However, under these circumstances, before the development of the slight acidity necessary for the prevention of side reactions, a minute proportion of undesired compounds, such as vinyl halides may be produced. To avoid these side reactions, it is preferred that the reaction mixture be acidulated at the beginning. i

'Ihe conditions of reaction above described are applicable to other olefin halide compounds of the classes' of polyhalides and halohydrins., such as trimethylene dibromide or dichloride, propylene chlorhydrin, trichloropropane and the like.

The rate of reaction may be increased and the time required for its completion shortened by the presence in the reaction mixture of heavy metals and of compounds thereof. Thus titanium, titanium oxide, vanadium, vanadium chloride,

gold, silver, platinumfmercury and their soluble or insoluble salts have been found to markedly accelerate the reaction. The metals or insolublel compounds thereof are preferred, since theyfmay be more readily separated from the reaction mix-A ture. The heavy metals of therst and second groups,.sueh as si1ver,.gold, and mercury. and those of the gold period, such as osmiurn, platinum, gold and mercury have been found particularly effective.

strip of metallic gold or gold filings, the rate of reaction may be markedly accelerated and the reaction completed in two to two and one-half hours at temperatures of 160 to 170 C.v

As hereinbei'ore indicated, minute proportions of aldehydes may be found-in the reaction mixture at the end of the reaction. I have found' that the slight oxidation resulting in the formation of these aldehydes may be largely or entirely prevented by incorporating a very small amount of a reducing agent in the reaction mixture, such as metallic magnesium, iron or zinc, sodium bisulflte, potassium metabisulfite, acid Asodium phosphate or the like. In reacting upon the higher homologues ofv the ethylene dihalides or ethylene halohydrins for the production of higher polyhydric alcohols, it is found that the reaction requires a somewhat longer time and the most desirable temperatures for operation are somewhat higher than with the corresponding ethylene compounds. Thus, in reacting uponv trimethylene dichloride, although the reaction procee'ds at temperatures from 125 to 135 C. up, my preferred temperatures of opera-tion are in the order of 175 to 185 C. and a somewhat longer period of timeisrequired for completion of the reaction. In general, a less time for reaction is required when the halohydrins are employed than when the polyhalides are used.

The use of considerable excesses of water appear to inhibit decomposition and polymerization and reduce the formation of tarry and resinous bodies. Thus, although the lreaction may be satisfactorily conducted with a volume of water ve to ten times as great as the volume of the as hydrochloric acid vapors and eth iene df"- chloride vapors through a continuous passage or coil in which a temperature in excess of 125 to 135 C. and preferably of 160 to 175 C. is main- Thus, by vincorporating in the reaction mixture above specifically set forth a` tained. The coil may suitably be packed with any refractory packing material, such as ceramic mashown.

The olefin dihalide, as for example, ethylene dichloride, is forced by pump Iii, from any suitable source of supply to a pressure feed tank II. Heated Water, preferably acidulated as hereinbefore described, from any suitable source oi supply, is pumped by a pump I2, to a pressure 'feed tank I3. These liquids in the tanks Il and I3 are maintained under sufficient pressure t0 secure theproper feed. Predetermined amounts of ethylene dichloride and heated acidulated water, are then metered under pressure through the meters III and I5 respectively, to a heat ex-` changer I6 through a common line Il. In general, the reacting constituents are controlled so as to be maintained in the same relative proportions as hereinbefore set forth in connection with flic the batch operation. The mixture of ethylene f dichloride and acidulated water is thus brought to a temperature at which a reaction may begin 'and the mixture then flows through the line I into the reaction chamber i9. The reaction chamber is maintained at a temperature in excess .of 125 to 135 C. and preferably at 160 to 175 C., although temperatures as high at 200" C. may be used. This chamber may, if desired. be packed with refractory material, preferably interspersed or coated with a catalyst as hereinabove set forth. 'Ihe chamber is also lined with such catalytic material, preferably silver. 'I'he reaction of the mixture there takes place under heat and pressure. Reaction products, in vapor'form, then flow through the column 20' wherein entrainment is separated and some reflux occurs, and then through a pressure reducing valve 2i. 'I'he vapors are then subjected to fractionation, prefera-bly under vacuum in a manner to be described.

If desired, a circulating line 22 and a pump 23.

maybe providedfor recirculatingwthe reaction mixture and reacted products through the reaction chamber I9. This is advisable at the start of the operation, and has been found to be desirable throughout the reaction to build up the available concentration of glycol in this reaction' mixture. A y

The line 22 is provided with valved openings at different levels into chamber I9, for withdrawal of its contents at one or more levels. Thus either one or both of the two upper valves maybe opened while maintaining the lower one closed to recirculate the aqueous reaction products through the line 22 and the reaction chamber I9; or, if desired, all the valves may be opened and uriconsumed ethylene dichloride and aqueous reaction mixture may be recirculated in the desired controlled proportions, for example, in initially bringingl the reaction mixture to the de-v sired reaction condition.

The reaction chamber may be heated to the desired temperature by any suitable means, as

f by a coil through which iiows a circulating heated uid as for example, oil, diphenyl or the like.- The heating medium is circulated in the direction ofthe arrows in a closed circuit, as by pump 24 through the heating coils 25 in a furnace 26, through the coils surrounding the reaction chamber I9, through the heat exchanger I6 and back to the heating coils. A portion of the heated oil entering the reaction chamber may be diverted in any suitable manner to the lower part of a dephlegmating tower or column 2 1, through a coil or reboiler 30, wherein it reheats condensate formed in the column 21 as hereinafter described. Suitable by-passes 28 and 29 may beprovided in the closed heating line for the purpose of controlling the temperature of the reaction chamber I9 and the reboiler 39 respectively.

The apparatus so fas described (up to the pressure reducing valve 2 I) constitutes the high pressure side bf the apparatus wherein a pressure in the order of, for example, 200-225 lbs. per square 1nch and a temperature in excess of 125 to 135 C. and up to 200 C. may be maintained. The apparatus to the right of the pressure reducing valve constitutes the low pressure side wherein a pressure in the order of, for example, 20-30 lbs. or lower, or a vacuum may be maintained.

As stated above, vapor reaction products leave the reaction chamber through column 2li! and pass through the reducing valve 2l into the low pressure side of the apparatus. These vapor reaction products then pass into the dephlegmating column 21 wherein the higher boiling point vapors are condensed, a cooling medium being passed through a cooling coil 3l in the upper part of column 21. The cooling medium may be cold acidulated water supplied wholly or in part from a collector or cooler 32, through a main water supply line 33, and a line 39 tapped therefrom, in any desirable manner, as by a pump 34. The oleiin polyhydroxide condensate. ,as for example ethylene glycol, usually with some water, flows from the dephlegmating tower 21 through water cooler 35 and subsequently into a glass-lined or non-corrodible storage tank 38. The top temperature maintained in column 21 by the water flowing through the coil 3l is preferably low enough to condense out substantially all of the ethylene glycol contained inthe vapors. Lower boiling constituents are stripped from the glycol or glycol solution in the base of tower 21 by suitable control of its temperature by reheater coil 30. 'I'he uncondensed vapors rise in the dephlegmating tower 21 and pass/through a line 31 into a second dephlegmating column 38.

Water may be supplied to the cooler 35 through a line 40 tapped from the line 39. This water becomes heated byindirect heat exchange with the condensate owing through the cooler 35 and is passed through a line 4I wherein it is mingled with the heated water owing from the coil 3|. This combined stream of acidulated water has a temperature in the order of say 75 to 85 C. and is introduced, through a suitable valve arrangement, into the system through the line 42 leading to the intake of pump I2.

The uncondensed vapors issuing from the tower 21 are introduced into the tower 38, wherein the high boiling vapors are condensed, suitable temperatures being maintained by a cooling coil 43 through which water, tapped from the cold water supply line 33, flows. The condensed vapors, an aqueous solution of hydrochloric acidof about 20% concentration, flows from the tower 38 through a cooler 44 and subsequently into a rubber-lined or non-corrodible storage tank 45. The cooler 44 is supplied with cold water from the supply line 33 and the heated water issuing therefrom is mingled with the water issuing from the coil 43 and may ow through lines 46 and 42 to the intake of pump I2 or directed to cooler or collector 32 as hereinafter described.

The uncondensed vapors issuing from the tower 38 pass through a line 41 into a dephlegmating tower 48, in which a dilute aqueous solution of Ycooler 44 and coil 49 and cooler 50 may be introduced into the system through the intake of pump I2 along with the water fromv line 4I or may be diverted to the cooler 32, To accomplish this I may suitably provide a valve 64 and valves 65, 66 and 61 in the lines 42 and 46 respectively to eiect this arrangement. Thus if valve G is closed and valves 64, 66 and 61 open, the water from line 4I will flow to the intake of pump I2 through line 42 and the water issuing from the coil 43 and cooler 44 and coil 49 and cooler 50 i will flow through line 46 to the cooler or collector 32. Now if valve 65 is opened and valve 66 is clesedf/the water from the coil d3 and cooler'li will flow through the lines 46 and 42 to the incooler 44 and coil 49 and cooler 50 will flowl through the system. It is apparent that the ow of water to the system, from the coils and coolers, may be controlled at will and to suit the desired need by a simple adjustment of the valves.

The uncondensed vapors issuing from the tower 48 pass through a line 52 in a dephlegmating tower 53. These 'vapors now consist primarily of ethylene chlorhydrin, unconsumed ethylene dichloride carried over by steam distillation, and some water. In the tower 53 the ethylene chlorhydrin and uncondensed ethylene dichloride are condensed, the required temperature being maintained by the cooling coil 54 which is supplied with Water from the line 33. The condensate flows into a water cooler 55, cooled by water from the line 33, and subsequently into a rubber-lined or non-corrodible storage tank 56.' If desired, this condensate may be returned to the feed tank I3 along with the fresh charge of heated water, and thus into the system, by means of a valve 51 and a line 58. yThe water issuing from the coil 54 is returned to the cooler 32 through a line 58 and line 46 and the water from the cooler 55 is returned directlyV to the cooler 32 through a line 6B. l

The vapor issuing from the tower 53, substantially all water vapor, ows through a line 6I to a condenser B2, wherein it is condensed and the condensate to a receiver 63 and subsequently to the cooler 32. The vent of receiver 63 may be vented to the atmosphere or connected to a suitable vacuum producing apparatus as for example, a vacuum. pump (not shown) which operates continuously on the system so that the low pressure side thereof is maintained at a relatively low pressure, say atmospheric or at a vacuum in the order of 10 to 20 in.v In this manner, fractional separation of the constituents takes place at a relatively low pressure.

The heated Water from the coils-43, 49 and 54 and the water coolers M, 50 and 55 is returned to the cooler 32, although it may be introduced into the system by a suitable control of the valves, in the manner afbove described, along with the Water from the coil 3| and the cooler 35. I prefer the former arrangement however, because the initial acidity of the Water as Well as the temperature, may be more readily controlled inthe cooler 32. Suitable arrangements can be provided in connection with the cooler 32 to control the acidity of the water therein, the temperature thereof and to replace the water consumed in the system. v

' The process of my invention may be carried out in a continuous manner. Thus, in accordance with this invention, ethylene dichloride is heated under vpressure with an excess of water, say at least ten times its volume and preferably about fifteen to twenty times its volume and the mixture heated under pressure in the reaction chamber i9v until uniform reaction has taken place. The vapor reaction products are then subjected to fractional condensation under reduced pres-,- sure to remove the various constituents of the vapors as for'example the glycol, the acid in aqueous solution and the ethylene chlorhydrin and any unconsumed ethylene dichloride. The ethylene chlorhydrin and unconsumed ethylene dichloride may be returned to the system through the line 58 for further treatment and completion gf the reaction in the manner described.

In operating the process, I prefer to utilize a ratio of water to ethylene dichloride of say 10 to 1,

or higher. The ethylene dichloride and water are supplied in the desired proportions for tanks li and iand the chlorhydrin formed in the system is recycled. The reaction mixture is passed slowly through the reaction chamber, say in the order of about 60 minutes, in order to insure unlform reaction, and the aqueous reaction products may, if desired, be recycled in the manner described above. If desired, the acid from the tanks d and 5i may be adjusted to the desired acidity and recycled with the incoming stream of reagents. As stated above, the acidulation'of the l reaction mixture at the beginning of the operation is desirable for the purpose of preventing the formation of undesired compounds, such as vinyl .compounds and the like.

In carrying out the reaction\as hereinbefore described, the aqueous reaction mixture resulting from the reaction has a relatively low proportion of glycol present, which must be separated It has in the low pressure distillation process. been found in accordance with the present invention that the concentration of glycol in the reaction mixture niay be readily increased by slowly and progressively adding the ethylene dichloride to the water in the reaction chamber. .In this semi-continuous or progressive feeding operation, the proportion of ethylene dichloride consumed is increased, and there is a corresponding increase of glycol formed in a given quantity. of aqueous liquid present in the reaction mixture while maintaining high efficiency of glycol formation,

' y notwithstanding the progressively increasing acid aisdsoi reaction mixture in aliquot or approximately aliquot proportions or may be added slowly and continuously as the ethylene dichloride present is consumed, thus maintaining a desired ratio or proportion between the ethylene dichloride and.

aqueous liquid present in the reaction mixture.

-Thus by adding the ethylene dichloride in this manner, and maintaining a ratio of between 9:1

and :1 of aqueous liquid to ethylene dichloride,

I have been' able to build up the glycol concentration of the aqueousliquid to approximately 10 to 15% while maintaining a high yield eiliciency notwithstanding the increase of the acid concentration to approximately 17 to.20% HC1 in the same period.

Thus, in carrying out the reaction in the apparatus disclosed in the drawing, the aqueous liquid, which may include chlorhydrins and acid derived from previous operation as previously described, may be charged into reaction vessel le with a suitable proportion o ethylene dichloride to establish a desired ratio of say-'about 10 to 1. Reaction is initiated as heretofore described, with or without recirculation of the reaction mixture. It is then continued under the temperature and pressure conditions heretofore set forth and Without withdrawal of liquid or vapor products, with continuous or intermittent introduction of additional ethylene dichloride as the dichloride is consumed, until a desired concentration of glycol, say 10% or higher, is secured in the aqueous liquid. The supply of ethylene dichloride may then be discontinued, the unconsumed dichloride withdrawn, and vthe products distilled from the' heretofore described.

I claim:

1. In the Amethod of producing glycoL-the steps I comprising admixing. ethylene dichloride with Water, heating a body of the mixture-under pressure to a temperature in excess of 125 C. in a closed vessel, withdrawing aqueous reaction products from said Vessel and recycling the aqueous reaction products through said vessel.

2. In the method of producing glycol, the stepscomprising admixing ethylene dichloride with water, heating a body of the mixture under pressure to a temperature in excess of 125 C. in a closed vessel, withdrawing aqueous reaction products and unconsumed ethylene dichloride from said vessel and recycling them through said vessel. 3. In the method of producing glycol,l the steps comprising admiinng ethylene dichloride with water, heating a body of the mixture under pressureto a temperature in excess of 125 C. in a closed vessel,'withdrawing aqueous reaction products` and unconsumed ethylene dichloride in controlled proportions from said vessel and recycling them through said vessel.

4. In the method of producing glycol, the steps comprising admixing ethylene dichloride with water, heating a body of the'mixture under pressure to a temperature in excess of 125 C, in a closed vessel, and in the presence of free acid, withdrawing aqueous reaction products from said vessel and -recycling the aqueous reaction products through said vessel.

5. In the method of producing glycol, the steps comprising admixing ethylene dichloride with water. heating a body of the mixture under pressure to a temperature in excess of 125 C. in aclosed vessel, and in the presence of free acid, withdrawing aqueous reaction products and unconsumed ethylene dichloride from said vessel and'recycling them through said vessel.

6. 'I'he method of producing glycol which comprises admixing ethylene dichloride with water, heating a body of the mixture under pressure to a temperature in excess of 125 C. in a closed vessel, withdrawing aqueous reaction products from said vessel and recycling them through said vessel and simultaneously withdrawing vaporous reaction products from said vessel, removing hy- -drolyzed products from said vaporous reaction ing the qhlorhydrins to the said body of the mixture.

8. The method o'f producing glycol which comprises admixing ethylene dichloride with water, heating a body of the mixture. to a temperature in excess of 125 C. to form a vaporous reacted mixture, withdrawing the vaporous reacted mixture and removing hydrolyzed products therefrom, separating chlorhydrins from said hydrolyzed products and returning the'chlorhydrins to the said body of the mixture.v

9. The continuous methgd of producing glycol which comprises admixing ethylene dichloride with water,.heating a body of the mixture under pressure to a temperature in excess of 125 C. to.- form a vaporous reacted mixture, withdrawing the vaporous reacted mixture and removingl hydrolyzed products therefrom, separating chlorhydrins from said hydrolyzed products and returning the chlorhydrins to the said body of the mixture.

10. The method of producing glycol which comprises forcing into a reaction vessel a continuous stream of ethylene dichloride and water, the

-volumetric proportion of the water being from ing frompthe reaction Vessel a continuous stream .of vaporous reaction products; separating from the stream thus withdrawn the glycol and. chlorhydrin to the chamber with the entering stream of reagents for further treatment in an acid reaction mixture and formation oi' additional glycol. K

11. The method of producing glycol which comprises forcing into a reaction vessel a continuous stream' ofethylene dichloride and water, the yolumetric proportion of the water being from 10 to 20 times 4that of the ethylene dfichloride, maintaining a body of said mixture in -the reaction vessel` at a temperature above 1359 C.

and below 200v C. and at 9T pressure of 20D-225 lbs. per square inch, whereby glycols, free hydrochloric acid and chlorhydrin are formed in said reaction mixture, and conducting saijd reaction without diminution of hydrochloric formed by neutralization, withdrawing from the reaction vessel a continuous stream of vaporous reaction products, separating from the stream thus withdrawn the glycol and chlorhydrin andbreturning the chlorhydrin to the chamber with the entering stream of reagents for further treatment in an acid reaction mixture and formation of additional glycols.

12. The method of producing glycol which comprises forcing into a reaction vessel a ccn- .tinuous stream of ethylene dichloride and water,

the volumetric proportion of the water being fron 10 to 20 times that of the ethylene dichloride, maintaining ya body oi said mixture inthe reaction vessel at a temperature of 150 to 175 C. and at. a pressure of 200-225 lbs. per square inch, whereby glycols, free hydrochloric acid and chlorhydrin are formed in said reaction mixture, and conducting saidI reaction without diminution of hydrochloric formed by neutralization, withdrawing from the reaction vessel a. continuous stream oi' vaporous reaction products, sepa-Y rating from the stream thus withdrawn the glycol and chlorhydrin and returning the chlorhydrin to the chamber with the entering stream of reagents for further treatment in an acid reaction mixture and formation of additional glycol.

13. The method oi' producing glycol which comprises forcing into a reaction vessel a continuous stream of ethylene .dichloride and water, the volumetric proportionY of the water being 15 times that of the ethylene dichloride, maintaining a body of said mixture in the reaction vessel at a temperature above 135 C. and below 200 C., whereby glycols, free hydrochloric acid and chlorhydrin are formed in said reaction mixture, and conducting said reaction without diminution of hydrochloric formed by neutralization,

withdrawing from the reaction vessel a continuous stream oi' vaporous reaction products, separating from the stream thus withdrawn the glycol and chlorhydrin and returning the chlorhydrin to the chamber with the entering stream of reagents for further treatment in an acid reaction mixture and formation of additional glycol.

14. A"l'he method of producing glycol which comprises forcing into a reaction vessel a. continuous stream of ethylene dichloride and water, the volumetric proportion of the water being 15 times that -of the ethylene dichloride, maintaining a body of said mixture in the reaction vessel at a temperature of 160 to 175 C., whereby glycols, free hydrochloric lacid and chlorhydrin are formed in said reaction mixture, and conducting said reaction without diminution of hydrochloric formed by neutralization, withdrawing from the reaction vessel a continuous stream of vaporous reaction products,` separating from the. stream thus withdrawn the glycol and chlorhydrin and returning the chlorhydrin to the chamber with the entering stream of reagents for further treatment in an acid reaction mixture and formation of additional glycol.

15. The method oi producing glycol which comprises admixing continuousstreams of ethylene dichloride and water, heating a body of the mixture under pressure to a temperature inA excess .of 135 C. in the presence oi free acid, withdrawing vaporous reaction products therefrom, separating chlorhydrin from said reaction products at a relatively lower temperature and pressure and returning nthe chlorhydrin with the entering stream of reagents for further treatment. I

16. The method oi producing glycol which comprises admixing continuousstreams of ethylene dichloride and water, heating a body of the mixture to a temperature in excess of 135 C. and at a pressure of from 20d-225 lbs. per square inch, withdrawing reaction products therefrom, separating chlorhydrin from said reaction products at a temperature below 135. and at a pressure of from 20-30 lbs. per square inch andreturning the chlorhydrin with the entering stream of reagents for further treatment.

17. The method of producing glycol which comprises admixing continuous streams of ethylene dichloride and water, heating a body of the mixture to a temperature in excess of 135 C. and at a pressure of from 20o-225 lbs. per square inch in the presence of free acid, withdrawing reaction products therefrom, separating chlorhydrin from said reaction products at a temperature below 135 C. and at a pressure of from 20-30 lbs. per square inch and returning v'the chlorhydrin with the entering stream ment.

18. 'Ihe method of producing glycol which comprises admixing ethylene dichloride with water, heating a body of the mixture under pressure to a temperature-in excess of C., withdrawing vaporous reacted mixture and removing hydrolyzed products therefrom, separating chlorhydrins from said hydrolyzed products and returning the chlorhydrins to the said body of thes mixture.

19. The method of producing glycol which comprises admixing ethylene dichloride with watenheating a body of the mixture under pressure to a temperature in excess of 125 C. in the presence of free acid, supplying additional ethylene dichloride and water to the mixture, withdrawing 'vaporous reaction products therefrom, removing hydrolyzed products from the separated reaction mixture, separating chlorhydrins from said hydrolyzed products, and returning the chlorhydrins to the said body of the mixture.

' 20. The method of producing glycol which comprises forcing into a .reaction vessel a continuous stream ofethylene dichloride and water, the volumetric proportion ofthe water being from 10 to 20 times that' of the ethylene dichloride maintaining a body oi said mixture in the reaction vessel at a temperature above C. and below 200 0. whereby glycols, free hydrochloric acid 'and chlorhydrin are formed in said reaction mixture. and conducting said reaction without diminution of hydrochloric formed by neutralization. withdrawing from the reaction vessel a continuof reagents for further treatalsmaar ous stream of the vaporous reaction products, separating from the stream thus withdrawn the glycol and chlorhydrin and returning the chlorhydrin to the chamber with the 'entering stream of reagents for further treatment inan acid reaction mixture and formation of additional' glycol.

2l.. In the method of producing glycol, the steps comprising reacting al desired ratio of ethylene dichloride and an aqueous liquid in a reaction ohamber while maintaining the reactants under pressure and at a temperature in excess of 125 C., slowly feeding ethylene dichloride to the reaction chamber to replace the ethylene dichloride consumed in the reaction and thereby maintain the desired ratio between the reactants, and

' subsequently removing reaction products from said chamber. 22. In' the method of producing glycol, the

'steps comprising reacting a desired ratio of ethylene dichloride and an aqueous liquid in a reaction chamber while maintaining the reactants under pressure and at a temperature in excess of 125 C., slowly and continuously feedingethylene dichloride to the reaction vchamber to r'eplace the ethylene dichloride consumed inv the reaction and thereby maintain the desired ratio between the reactants, and subsequently removing reaction products from said chamber.

tain the desired ratio betwen the reactants, and subsequently removing vaporous reaction products from said reaction chamber.

24. In the method of producing g1yco1, thesteps comprising reacting a desired ratio Yof ethylene dichloride and an aqueous liquid in a reaction chamber whi/le maintaining the reactants under pressure and at. a temperature in excess of 125 C., slowly and continuously feeding ethylene dichloride to the reaction chamber to replace the ethylene dichloride consumed in the lreaction and thereby maintain the desired ratio between the reactants, and subsequently removing vaporous reaction products from said chamber.

NATHAN M. MNOOKN.

ride consumed in the reaction and thereby mai'n- 

